index.js

/**
* Copyright 2012-2018, Plotly, Inc.
* All rights reserved.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/

'use strict';

var cluster = require('point-cluster');
var isNumeric = require('fast-isnumeric');

var ScatterGl = require('../scattergl');
var calcColorscales = require('../scatter/colorscale_calc');
var calcMarkerSize = require('../scatter/calc').calcMarkerSize;
var Axes = require('../../plots/cartesian/axes');
var makeHoverPointText = require('../scatterpolar/hover').makeHoverPointText;
var subTypes = require('../scatter/subtypes');

var TOO_MANY_POINTS = require('../scattergl/constants').TOO_MANY_POINTS;

function calc(container, trace) {
    var layout = container._fullLayout;
    var subplotId = trace.subplot;
    var radialAxis = layout[subplotId].radialaxis;
    var angularAxis = layout[subplotId].angularaxis;
    var rArray = radialAxis.makeCalcdata(trace, 'r');
    var thetaArray = angularAxis.makeCalcdata(trace, 'theta');
    var len = trace._length;
    var stash = {};

    if(len < rArray.length) rArray = rArray.slice(0, len);
    if(len < thetaArray.length) thetaArray = thetaArray.slice(0, len);

    stash.r = rArray;
    stash.theta = thetaArray;

    // We could add TOO_MANY_POINTS logic like in Scattergl.calc,
    // if users asks for scaterpolargl charts with > 1e5 pts
    var ppad = calcMarkerSize(trace, len);
    trace._extremes.x = Axes.findExtremes(radialAxis, rArray, {ppad: ppad});

    calcColorscales(trace);

    return [{x: false, y: false, t: stash, trace: trace}];
}

function plot(container, subplot, cdata) {
    if(!cdata.length) return;

    var radialAxis = subplot.radialAxis;
    var angularAxis = subplot.angularAxis;

    var scene = ScatterGl.sceneUpdate(container, subplot);

    cdata.forEach(function(cdscatter, traceIndex) {
        if(!cdscatter || !cdscatter[0] || !cdscatter[0].trace) return;
        var cd = cdscatter[0];
        var trace = cd.trace;
        var stash = cd.t;
        var len = trace._length;
        var rArray = stash.r;
        var thetaArray = stash.theta;
        var i;

        var subRArray = rArray.slice();
        var subThetaArray = thetaArray.slice();

        // filter out by range
        for(i = 0; i < rArray.length; i++) {
            if(!subplot.isPtInside({r: rArray[i], theta: thetaArray[i]})) {
                subRArray[i] = NaN;
                subThetaArray[i] = NaN;
            }
        }

        var positions = new Array(len * 2);
        var x = Array(len);
        var y = Array(len);

        for(i = 0; i < len; i++) {
            var r = subRArray[i];
            var xx, yy;

            if(isNumeric(r)) {
                var rg = radialAxis.c2g(r);
                var thetag = angularAxis.c2g(subThetaArray[i], trace.thetaunit);
                xx = rg * Math.cos(thetag);
                yy = rg * Math.sin(thetag);
            } else {
                xx = yy = NaN;
            }
            x[i] = positions[i * 2] = xx;
            y[i] = positions[i * 2 + 1] = yy;
        }

        var options = ScatterGl.sceneOptions(container, subplot, trace, positions);

        // set flags to create scene renderers
        if(options.fill && !scene.fill2d) scene.fill2d = true;
        if(options.marker && !scene.scatter2d) scene.scatter2d = true;
        if(options.line && !scene.line2d) scene.line2d = true;
        if((options.errorX || options.errorY) && !scene.error2d) scene.error2d = true;
        if(options.text && !scene.glText) scene.glText = true;

        stash.tree = cluster(positions);

        // FIXME: see scattergl.js#109
        if(options.marker && count >= TOO_MANY_POINTS) {
            options.marker.cluster = stash.tree;
        }

        // bring positions to selected/unselected options
        if(subTypes.hasMarkers(trace)) {
            options.markerSel.positions = options.markerUnsel.positions = options.marker.positions;
        }

        // save scene options batch
        scene.lineOptions.push(options.line);
        scene.errorXOptions.push(options.errorX);
        scene.errorYOptions.push(options.errorY);
        scene.fillOptions.push(options.fill);
        scene.markerOptions.push(options.marker);
        scene.markerSelectedOptions.push(options.markerSel);
        scene.markerUnselectedOptions.push(options.markerUnsel);
        scene.textOptions.push(options.text);
        scene.textSelectedOptions.push(options.textSel);
        scene.textUnselectedOptions.push(options.textUnsel);
        scene.count = cdata.length;

        // stash scene ref
        stash._scene = scene;
        stash.index = traceIndex;
        stash.x = x;
        stash.y = y;
        stash.rawx = x;
        stash.rawy = y;
        stash.r = rArray;
        stash.theta = thetaArray;
        stash.positions = positions;
    });

    return ScatterGl.plot(container, subplot, cdata);
}

function hoverPoints(pointData, xval, yval, hovermode) {
    var cd = pointData.cd;
    var stash = cd[0].t;
    var rArray = stash.r;
    var thetaArray = stash.theta;

    var scatterPointData = ScatterGl.hoverPoints(pointData, xval, yval, hovermode);
    if(!scatterPointData || scatterPointData[0].index === false) return;

    var newPointData = scatterPointData[0];

    if(newPointData.index === undefined) {
        return scatterPointData;
    }

    var subplot = pointData.subplot;
    var cdi = newPointData.cd[newPointData.index];
    var trace = newPointData.trace;

    // augment pointData with r/theta param
    cdi.r = rArray[newPointData.index];
    cdi.theta = thetaArray[newPointData.index];

    if(!subplot.isPtInside(cdi)) return;

    newPointData.xLabelVal = undefined;
    newPointData.yLabelVal = undefined;
    makeHoverPointText(cdi, trace, subplot, newPointData);

    return scatterPointData;
}

module.exports = {
    moduleType: 'trace',
    name: 'scatterpolargl',
    basePlotModule: require('../../plots/polar'),
    categories: ['gl', 'regl', 'polar', 'symbols', 'showLegend', 'scatter-like'],

    attributes: require('./attributes'),
    supplyDefaults: require('./defaults'),
    colorbar: require('../scatter/marker_colorbar'),

    calc: calc,
    plot: plot,
    hoverPoints: hoverPoints,
    selectPoints: ScatterGl.selectPoints,

    meta: {
        hrName: 'scatter_polar_gl',
        description: [
            'The scatterpolargl trace type encompasses line charts, scatter charts, and bubble charts',
            'in polar coordinates using the WebGL plotting engine.',
            'The data visualized as scatter point or lines is set in',
            '`r` (radial) and `theta` (angular) coordinates',
            'Bubble charts are achieved by setting `marker.size` and/or `marker.color`',
            'to numerical arrays.'
        ].join(' ')
    }
};